Coalescence of Asymmetrically-arranged Droplets on Topographic Substrates

doi:10.19596/j.cnki.1001-246x.7628

Abstract

Abstract: Coalescence of two surfactant-containing droplets on a topographic substrate was modeled with lubrication theory considering asymmetrically-arranged configuration. Effects of initial droplet spacing and height of substrate on coalescence evolution were investigated and compared with symmetrically-arranged droplets. It shows that variation of droplet height undergoes five stages, and variation of surfactant concentration experiences three stages in a short period; Coalescing time of droplets and surfactant is extended with increasing droplet spacing while shorten with increasing substrate height; Coalescence time of asymmetric droplets is distinctly less than that of symmetric droplets, resulting in a faster rate of coalescence.

Key words: asymmetric droplets, coalescence, initial spacing, base height

CLC Number:

O354

LIN Yuxi, YE Xuemin, LU Lifang, LI Chunxi. Coalescence of Asymmetrically-arranged Droplets on Topographic Substrates[J]. CHINESE JOURNAL OF COMPUTATIONAL PHYSICS, 2018, 35(3): 275-284.

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